Purified thiocarbamate-inducible ThcF of Rhodococcus erythropolis NI86/21, overexpressed in Escherichia coli, displayed several characteristics of the HASH family of enzymes that groups prokaryotic proteins of the alpha/beta hydrolase superfamily possessing serine-dependent hydrolase and/or haloperoxidase activity. Kinetic analysis of bromination and ester hydrolysis revealed a low affinity of ThcF for model substrates. Sulfoxidation of thiocarbamates was demonstrated but probably represents a side activity due to peroxoacid generation by the enzyme. The thcF-linked thcG gene, encoding a LAL-type regulator, triggers expression of thcF in Rhodococcus. The tandem gene organization thcG-thcF is conserved in the thiocarbamate-degrading strain Rhodococcus sp. B30. It is proposed that HASH enzymes may be involved in the metabolism of plant-derived compounds.